<!DOCTYPE html>
<html lang="en">
	<head>
		<title>three.js webgpu - video panorama</title>
		<meta charset="utf-8">
		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
		<link type="text/css" rel="stylesheet" href="example.css">
		<style>
			body {
				touch-action: none;
			}
		</style>
	</head>
	<body>

		<div id="info">
			<a href="https://threejs.org/" target="_blank" rel="noopener" class="logo-link"></a>

			<div class="title-wrapper">
				<a href="https://threejs.org/" target="_blank" rel="noopener">three.js</a><span>Video Panorama</span>
			</div>

			<small>Video panorama using equirectangular projection.</small>
		</div>

		<div id="container"></div>

		<video id="video" loop muted crossOrigin="anonymous" playsinline style="display:none">
			<source src="textures/pano.webm">
			<source src="textures/pano.mp4">
		</video>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.webgpu.js",
					"three/webgpu": "../build/three.webgpu.js",
					"three/tsl": "../build/three.tsl.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three/webgpu';

			let camera, scene, renderer;

			let isUserInteracting = false,
				lon = 0, lat = 0,
				phi = 0, theta = 0,
				onPointerDownPointerX = 0,
				onPointerDownPointerY = 0,
				onPointerDownLon = 0,
				onPointerDownLat = 0;

			const distance = .5;

			init();

			function init() {

				const container = document.getElementById( 'container' );

				camera = new THREE.PerspectiveCamera( 75, window.innerWidth / window.innerHeight, .25, 10 );

				scene = new THREE.Scene();

				const geometry = new THREE.SphereGeometry( 5, 60, 40 );
				// invert the geometry on the x-axis so that all of the faces point inward
				geometry.scale( - 1, 1, 1 );

				const video = document.getElementById( 'video' );
				video.play();

				const texture = new THREE.VideoTexture( video );
				texture.colorSpace = THREE.SRGBColorSpace;
				const material = new THREE.MeshBasicMaterial( { map: texture } );

				const mesh = new THREE.Mesh( geometry, material );
				scene.add( mesh );

				renderer = new THREE.WebGPURenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.setAnimationLoop( animate );
				container.appendChild( renderer.domElement );

				document.addEventListener( 'pointerdown', onPointerDown );
				document.addEventListener( 'pointermove', onPointerMove );
				document.addEventListener( 'pointerup', onPointerUp );

				//

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			function onPointerDown( event ) {

				isUserInteracting = true;

				onPointerDownPointerX = event.clientX;
				onPointerDownPointerY = event.clientY;

				onPointerDownLon = lon;
				onPointerDownLat = lat;

			}

			function onPointerMove( event ) {

				if ( isUserInteracting === true ) {

					lon = ( onPointerDownPointerX - event.clientX ) * 0.1 + onPointerDownLon;
					lat = ( onPointerDownPointerY - event.clientY ) * 0.1 + onPointerDownLat;

				}

			}

			function onPointerUp() {

				isUserInteracting = false;

			}

			function animate() {

				update();

			}

			function update() {

				lat = Math.max( - 85, Math.min( 85, lat ) );
				phi = THREE.MathUtils.degToRad( 90 - lat );
				theta = THREE.MathUtils.degToRad( lon );

				camera.position.x = distance * Math.sin( phi ) * Math.cos( theta );
				camera.position.y = distance * Math.cos( phi );
				camera.position.z = distance * Math.sin( phi ) * Math.sin( theta );

				camera.lookAt( 0, 0, 0 );

				renderer.render( scene, camera );

			}

		</script>
	</body>
</html>
